The anti-tumor activity of live Streptococcus pyogenes bacteria (hereinafter S. pyogenes) has been known for many years. However, S. pyogenes includes most of the highly pathogenic strains of streptococci and can cause severe systemic and local infections. Consequently, live S. pyogenes bacteria have not been used to treat tumors because of their disease-causing potential.
The effective utilization of the anti-tumor activity of the pathogenic S. pyogenes is a problem that has not been solved satisfactorily. One approach has been to treat an attenuated strain of live S. pyogenes bacteria with a relatively high concentration of penicillin G. The treated S. pyogenes bacteria are then freeze-dried to produce the anti-cancer drug picibanil. However, this process requires the use of whole pathogenic bacteria as raw materials. The whole bacteria must be handled and maintained carefully and consistently to provide a stable supply of a usable product. This has proved difficult, and obtaining a consistent supply of a used anti-tumor agent from S. pyogenes has not heretofore been achieved.
A need exists, therefore, for a way to utilize the anti-tumor and other biological activity of S. pyogenes that does not have the drawbacks which accompany the production of the available anti-cancer product produced by whole S. pyogenes bacteria.